DC on input!
Hello Carlos!
To attack my DX Super A, i need an impedance matching circuit between the player and the amplifier and the Pass B1 fed symmetrical pleases me.
I have a question about the DC input on the DX.
The capacitor C38 surrounded on the images it protects the DC if a problem occurs in the B1?
Regards!
Hello Carlos!
To attack my DX Super A, i need an impedance matching circuit between the player and the amplifier and the Pass B1 fed symmetrical pleases me.
I have a question about the DC input on the DX.
The capacitor C38 surrounded on the images it protects the DC if a problem occurs in the B1?
Regards!
Attachments
The input capacitor you have highlighted and the 220uF electrolytic in the NFB path make this an AC coupled amplifier.
This is the safer way to drive your speakers.
Faults up stream don't blow up your speakers.
Only a serious fault inside the amplifier puts your speakers at risk.
That's where fuses and soft starting and temperature switches and speaker delay relay all come to your speakers' aid.
This is the safer way to drive your speakers.
Faults up stream don't blow up your speakers.
Only a serious fault inside the amplifier puts your speakers at risk.
That's where fuses and soft starting and temperature switches and speaker delay relay all come to your speakers' aid.
I'm not very sure of myself so I prefer to find out before making silliness. 😀
AndrewT thank you for that answer. 😉
AndrewT thank you for that answer. 😉
This capacitor blocks DC from the audio source
What is B1?
Is it a preamplifier?
Dx amplifier does not use preamplifiers..... if this is the case..they just kill the quality a little bit.
Plug your audio source direct to the power amplifier input.... this is for better results.
I do not know what is B1.... if it is a preamplifier...then please, do not use it....here a video about preamplifiers..what i think about them:
http://www.youtube.com/watch?v=VOJ4S9aTCPY
Carlos
What is B1?
Is it a preamplifier?
Dx amplifier does not use preamplifiers..... if this is the case..they just kill the quality a little bit.
Plug your audio source direct to the power amplifier input.... this is for better results.
I do not know what is B1.... if it is a preamplifier...then please, do not use it....here a video about preamplifiers..what i think about them:
http://www.youtube.com/watch?v=VOJ4S9aTCPY
Carlos
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No comment about the text
Dx amplifier does not need any preamplifier... just a potentiometer in the input.
I can point you the Aikido if you want a preamplifier...that one was tested...i will not test all preamplifier to inform what is junk and what is not junk.
Watch and listen the video below (signature line).... recorded with a cheap cell phone from Nokia.... even this way you can feel the quality...this is the sound the Dx amplifier can give you with a good audio source...a good recording sample.... with, and without a preamplifier.... if it can sound good without a preamplifier, i cannot see the point to use them.
I am having better sonics at home, with cheap speakers and no preamplifier...so, there's no point ot use them...i just have not a good recorder to show you the sample... all my recorders are worse than this cell phone.
If the guy want to use it, or need to use it...this is a matter of belief or faith, and this stuff is religion and not science and i would be happy not to discuss this.... my task is to inform this may not help and may harm your sound quality...so... advice is to avoid stages inside the audio chain.
This practice, to try preamplifiers or more stages inside the audio chain... may undermine and invalidate all the work I've been developing over many years ... and it worries me and upsets me.
The best preamplifier you can have is no preamplifier.
What this Aikido is making to the Dx Blame ST is to emphasize the second harmonic, as tubes use to do, and this i have already made in the Dx Super A, so, no need to emphasize what was already emphasized.... you may unballance by the wrong ratio.
regards,
Carlos
Dx amplifier does not need any preamplifier... just a potentiometer in the input.
I can point you the Aikido if you want a preamplifier...that one was tested...i will not test all preamplifier to inform what is junk and what is not junk.
Watch and listen the video below (signature line).... recorded with a cheap cell phone from Nokia.... even this way you can feel the quality...this is the sound the Dx amplifier can give you with a good audio source...a good recording sample.... with, and without a preamplifier.... if it can sound good without a preamplifier, i cannot see the point to use them.
I am having better sonics at home, with cheap speakers and no preamplifier...so, there's no point ot use them...i just have not a good recorder to show you the sample... all my recorders are worse than this cell phone.
If the guy want to use it, or need to use it...this is a matter of belief or faith, and this stuff is religion and not science and i would be happy not to discuss this.... my task is to inform this may not help and may harm your sound quality...so... advice is to avoid stages inside the audio chain.
This practice, to try preamplifiers or more stages inside the audio chain... may undermine and invalidate all the work I've been developing over many years ... and it worries me and upsets me.
The best preamplifier you can have is no preamplifier.
What this Aikido is making to the Dx Blame ST is to emphasize the second harmonic, as tubes use to do, and this i have already made in the Dx Super A, so, no need to emphasize what was already emphasized.... you may unballance by the wrong ratio.
regards,
Carlos
Attachments
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You may need to reduce your volume IF your audio source cannot do that
That's the reason of the potentiometer use.
If you can control the volume in your audio source, then remove the input potentiometer that gonna be a very good idea.
regards,
Carlos
That's the reason of the potentiometer use.
If you can control the volume in your audio source, then remove the input potentiometer that gonna be a very good idea.
regards,
Carlos
0.o_ again ? one simple comment, just drop one of this that all you need "in my opinion of course" 😉 feel free is ok.
Regards
Juan
Regards
Juan
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My audio source is a CD player. It has no volume adjustment. So what pot are you using at the input of the amp that does not alter the sound?
You can use any 50K or 100K potentiometer you find
wire it with the most short connections you can, a good shielded cable for audio and be happy.
Thank you forgiven, as you gave me the oportunity, together dear Project 16, to open my big mouth.
"Avoid preamplifiers video message to Corporation members":
http://www.youtube.com/watch?v=jLUgKzNzbtA
Carlos
wire it with the most short connections you can, a good shielded cable for audio and be happy.
Thank you forgiven, as you gave me the oportunity, together dear Project 16, to open my big mouth.
"Avoid preamplifiers video message to Corporation members":
http://www.youtube.com/watch?v=jLUgKzNzbtA
Carlos
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I agree with you Carlos! I have build some amps with just good pot to adjust volume and they sound so good. I have try using many sources like: dvd, iPod, laptop, pc, mp3 and they played without hiccups. I guess it is in the design and gain of amp and the output of source. People always say the problem with impedance and inductance match. I build the B1 using matched transistors and top quality caps and I did not notice an improvement in the sound at all. What I do is I use the best quality potentiometer like TKD in line and I always try to use the shortest path from input to potentiometer and from potentiometer to amp board. and I use the shortest RCA cables from source to input of amp. This kind of passive integrated amplifiers are very well know. Just to name some: Acurus D100, Portal panache, Adcom, and Creek. but there are many, many more out here. if people do not use phono...go passive!!!
PS: In my M400 amp I use a 10K TKD pot.
PS: In my M400 amp I use a 10K TKD pot.
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They will not be happy with uncle charlie....but i have to say what is the real thing
The brotherhood of believers and mystics will get angry dear Vargas.
What i am saying is the same i heard from this man, in 1981, during a dinner.
The man is Akio Morita......do you know the guy?....so...he is not stupid.
Thank you Lanchile..... thank you too.
regards,
Carlos
The brotherhood of believers and mystics will get angry dear Vargas.
What i am saying is the same i heard from this man, in 1981, during a dinner.
The man is Akio Morita......do you know the guy?....so...he is not stupid.
Thank you Lanchile..... thank you too.
regards,
Carlos
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😀
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My tests were done with a double potentiometer 100K between the source and the amplifier and the return is great.
But I read somewhere that it would be better to fit a high impedance to a low impedance (buffer) and add the potentiometer.
Apparently it does nothing!
Regards!
this is how you get the output transistor idle current...
bias voltage to the input or base is measured somewhere else...
I am glad i could reach 62 years old healthy
Dx birthday - YouTube
Thank you all by the friendship, the respect and support.
regards,
Carlos
Dx birthday - YouTube
Thank you all by the friendship, the respect and support.
regards,
Carlos
Increase the setting of the quiescent currents!
Hello Carlos!
Currently I have 2.50V on resistance of 10 ohms setting and how my DX is apparently perfect but heat sinks not very hot.
Is it possible to increase this setting and here is what would bring more?
Regards!
Hello Carlos!
Currently I have 2.50V on resistance of 10 ohms setting and how my DX is apparently perfect but heat sinks not very hot.
Is it possible to increase this setting and here is what would bring more?
Regards!